This is one of those cases where you ABSOLUTELY, POSITIVELY MUST get your site support group involved. They can help trace the interaction between the regions and determine where the issue is. There are too many potential variables involved for someone on a forum, not working at your site, to even hazard a guess.

As I said, there are times when you MUST talk to the site support group. A forum can help with many issues, but not all of them -- sites can have things set up too many different ways for a forum to be able to provide definitive answers in some cases.